Photoshop retouching of underwater images

[Jay]

Becomes ...

[Jay]

I've only scratched the surface but the filters / process I am using are:

1. Auto adjust levels (gives a starting point. Can be ignored if the results are too extreme)

2. Applying an adjustment layer for each of the following:

a. Levels
b. Hue & Saturation
c. Colour Mixer

3. Applying the Unsharpen Mask in the Filters section.

Key to it is playing around and to use TIFF images so you can resave time and time again WITHOUT ANY LOSS.

Regards

Jay

[ian.smyth]

Certainly improves the quality of the images..just out of interest, what kind of camera setup where you using??

cheers

[Mdemon]

That really makes a difference!  Time to dig out Photoshop...

[Andy Phillips]

Hi Heads,

The trick is to know what is happening when you alter something like Hue / Saturation and Intensity. A trick for you, try to alter a colour in RGB using gamma and contrast only. Gamma alters the linerarity of the gray scale of the chosen channel without removing any information of the channel. Hue will alter the actual colour and can create uncomfortable effects. Also, the reason most compression techniques make altering colour difficult is they actually remove colour information by "bining" colour pixels together. The theory is that the eye is less effective at seperating subtle colour changes than changes in colour satuation or greyscale intensity.

Unsharp masking works by first bluring the channel using a low pass filter, then subtracting the blured data from the original file then applying a multiplication to increase the intensity values of the de-blured data. It can be very harsh. Try to increase the radius and use the  threshold to protect the values in the image data.

If you want more information please ask, this is what I do for a living, it has fascinated me for the better part of 15 years.

All the best,

Andrew

[Gunna Do]

Ohh great,
             even thou i have bugger all time left at night, now I am going to have to start learning photoshop, Which has sat untouched on my comp since new...
Gee thanxs Jay,
I suppose I can sleep between 2 and 4am   lol
awesome improvement thou, I am most impressed
well time to start learning
Steve

[Jay]

Originally Posted by [b

Quote[/b] (AndyP @ July 21 2003,01:06)]Hi Heads,

The trick is to know what is happening when you alter something like Hue / Saturation and Intensity. A trick for you, try to alter a colour in RGB using gamma and contrast only. Gamma alters the linerarity of the gray scale of the chosen channel without removing any information of the channel. Hue will alter the actual colour and can create uncomfortable effects. Also, the reason most compression techniques make altering colour difficult is they actually remove colour information by "bining" colour pixels together. The theory is that the eye is less effective at seperating subtle colour changes than changes in colour satuation or greyscale intensity.

Unsharp masking works by first bluring the channel using a low pass filter, then subtracting the blured data from the original file then applying a multiplication to increase the intensity values of the de-blured data. It can be very harsh. Try to increase the radius and use the  threshold to protect the values in the image data.

If you want more information please ask, this is what I do for a living, it has fascinated me for the better part of 15 years.

All the best,

Andrew

Superb Andy - don't suppose you fancy doing a PS Tutorial using examples to show us how its done? I'm just starting to scratch the surface and I have seen some stunning images elsewhere.

[Andy Phillips]

Hi,

Going on a family holiday on Wednesday, but when I get back no probs.

Andrew

[JohnK]

Ahhh - Photoshop - its great !!!!

Just got back from lanzarote and will be posting some more piccies after I`ve run em thru photoshop.

Great hol, good diving and trip report will follow.